1. Field of the Invention
The field of the invention is that of controls for flow of gas in gas fired heating systems. The invention is particularly concerned with the pilot control of the main gas valves and all of the other control components by using a boosted gas pressure as the motive fluid.
2. Description of the Prior Art
Control valves and gas fired systems originally were electro-mechanical until another generation of control valves developed which were of an electro-hydraulic type, one of them having been known as the Hydramotor and also one known as Fluid Power Unit. This unit used a different motive fluid embodying hermetric pump and metal bellows.
It appears that the electro-hydraulic unit generally dominates the market world wide currently except for some large direct solid/magnetic units in Europe which are bulky, and large users of energy. They are inherently quick acting and have an inability to move slowly for modulating purposes and are otherwise deficient.
The prior art systems are expensive, heavier, and considered less adaptable than is desirable. They are deficient as respects all of the advantages set forth hereinafter possessed by the subject invention.